私 － watashi － I, Myself, ect.
の － no － of (possessive particle)
Looking it up in my Kanji dictionary I found:
最 － sai, motto(mo) － Most
後 － Go, Ko, Nochi, ushi(ro), ushiro, ato, oku(reru) － After
勝 － Sho, ka(tsu), -ga(chi), masa(ru) － Win / Excel
利 － ri, ki(ku) － advantage / profit
The kun readings: (I don't personally know what that is, but someone else may find it useful)
最 － mo
後 － go
勝 － masa, kachi, yoshi, suguru, suguri
利 － toshi, to, kaga, kazu, yoshi
All together:
私の最後の勝利
I can't figure it out (my best guess would be something like "My Greatest Prize"), but the kanji is here for someone with more experience.
I hope this helps.
